1. Field of the Invention
The disclosure relates generally to methods and systems for generating HDR (High Dynamic Range) images, and more particularly to methods and systems for generating HDR images based on frames with the same exposure time.
2. Description of the Related Art
Recently, portable devices, such as handheld devices, have become more and more technically advanced and multifunctional. For example, a handheld device may have telecommunications capabilities, e-mail message capabilities, image capture capabilities, an advanced address book management system, a media playback system, and various other functions. Due to increased, convenience and functions of the devices, these devices have become necessities of life.
Currently, a function called “HDR” or ‘HDRI (High Dynamic Range imaging)’ is provided on the portable devices, such as cameras. HDR is a method used in imaging and photography to allow a greater dynamic range between the lightest and darkest areas of an image than that of the traditional methods. HDR images can show more accurate range of intensity levels in real scenes.
Generally, non-HDR cameras take image frames at one exposure level, thus to obtain a limited contrast range. This results in the loss of detail in bright or dark areas of an image. In HDR methods, this loss of detail is compensated by taking multiple image frames at different exposure levels, and composing them together to generate an image that is representative in both dark and bright areas.
As described, in the HDR methods, a camera needs to take multiple image frames at different exposure levels. That is, the camera must support multi-frames, and have different camera exposure levels for capturing images. HDR is functionless for those cameras without the support of multi-frames, and having only one camera exposure level.